PLATE II. 
1. Hamites Ellipticus. ( Oval Hamite.) Compressed, with evenly undulating ribs, each with two small 
tubercles on outer margin ; curvature elliptical. 
2. H. Bucklandi. (BuckJanxTs Hamite.) Compressed, horn-shaped, much and gradually incurvated ; annu- 
lations, somewhat remote, slightly developed, oblique, nearly obsolete on inner margin. 
2 (a). Transverse section, showing lobes and saddles and siplmncle. 
3. H. Tuberculatus. {Tuberculated Hamite .) Compressed; gradually curved, unequal undulations, every 
third one larger than the others, with two obtuse tubercles on both sides, lateral ones somewhat obscure ; 
between each tuberculated ring usually two smaller ones. 
4. H. Adpressus. ( Adpressed Hamite.) Flattened in front, without annulations, lesser limb acute and 
pressed close to larger one ; surface smooth, with equidistant circles over whole shell, apparently septa. 
5. H. Nodosus. ( Knotty Hamite.) Nearly round, externally pearlaceous; with regular, annular undula¬ 
tions ; two rows of obtuse tubercles in front, each tubercle seated upon two of the rings, each pair of annula¬ 
tions with a simple one between them ; aperture somewhat ovate. 
6. H. Armatus. {Armed Hamite.) Depressed, with nearty regular, continuous, transverse, simple ridges, 
and a row of flattened tubercles next to interior margin, and another close to dorsal limb, connected by broad, 
high ridges ; on each side a series of these armed with long spines; limb of other side with simple tubercles ; 
ridges very indistinct on dorsal region. Greatest diameter, 1£ in. 
7. H. Rotundus. {Round Hamite.) Shell round, slightly and gradually curved ; with regular, somewhat 
obtuse, numerous annulations; aperture round. 
8. H. Turgidus. ( Turgid Hamite.) Compressed with abrupt, irregularly turgid front, with two rows of 
small tubercles on each side on every alternate annulation; regular annulations, obsolete on back, sometimes 
only one row of tubercles. 
9. H. Multicostatus. {Many-ribbed Hamite.) Sub-cylindrical; with numerous oblique, narrow ribs ; no 
appearance of tubercles. Diameter nearly 1J in. 
10. H. Plicatilis. {Folded Hamite.) Compressed, with numerous continuous, annular, undivided ridges ; 
each side with two rows of depressed, equal tubercles, extending over those of the annular ridges ; two ridges 
between each tubercle ; curvature gradual. 
11. H. Undulatus. {Waved Hamite.) Depressed; irregular transverse annulations with two rows of large, 
flattened tubercles ; curvature abrupt. 
12. H. Spiniger. (Spined Hamite.) Compressed ; numerous curved, slightly transverse, irregularly formed 
ridges; with two rows of sharp tubercles on each side, placed near dorsal limb ; aperture oval; curvature 
gradual. Maximum diameter, & in. 
13. H. Alternatus. {Alternating Hamite.) Sub-cylindrical; with distinct, oblique, annular ribs, obsolete 
in internal margin; with two rows of largish, marginal tubercles, placed on each alternate rib; curvature 
gradual. 
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